Systems and methods for hazard mitigation

Abstract

A system and method to avoid collisions on highways, and to minimize the fatalities, injury, and damage when a collision is unavoidable. The system includes sensor means to detect other vehicles, and computing means to evaluate when a collision is imminent and to determine whether the collision is avoidable. If the collision is avoidable by a sequence of controlled accelerations and decelerations and steering, the system implements that sequence of actions automatically. If the collision is unavoidable, a different sequence is implemented to minimize the overall harm of the unavoidable collision. The system further includes indirect mitigation steps such as flashing the brake lights automatically. An optional post-collision strategy is implemented to prevent secondary collisions, particularly if the driver is incapacitated. Adjustment means enable the driver to set the type and timing of automatic interventions.

What is claimed is: 
     
         1 . An arrangement for mitigating a forward collision between a host vehicle and an oncoming vehicle, the host vehicle having one or more sensors arranged to monitor a road ahead of the host vehicle and a braking system connected to wheel brakes thereof, the arrangement comprising:
 a vehicle forward collision threat evaluation system configured to:   utilize the one or more sensors to establish presence of an oncoming vehicle and estimate parameters associated with the oncoming vehicle,
 utilize the estimated parameters to predict a future path of the oncoming vehicle, 
 utilize host vehicle parameters to predict a future path of the host vehicle, and 
 assess the predicted future paths of the oncoming vehicle and of the host vehicle to determine if a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable assuming freedom for performing avoidance maneuvers for both the host vehicle and the oncoming vehicle in the prediction of the respective future paths of the host vehicle and the oncoming vehicle; and
 a forward collision mitigation brake controller configured to control the braking system to control wheel brakes of the host vehicle to reduce a relative longitudinal velocity between the host vehicle and the oncoming vehicle at a predicted collision instant if determined that a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable at a determined relative longitudinal velocity above a first threshold. 
 
   
     
     
         2 . The arrangement according to  claim 1  wherein the estimated parameters include one or more of distance between the oncoming vehicle and the host vehicle, lateral and longitudinal velocity of the oncoming vehicle, relative longitudinal velocity between the host vehicle and the oncoming road vehicle, and lateral and longitudinal acceleration of the oncoming vehicle. 
     
     
         3 . The arrangement according to  claim 1  wherein the forward collision mitigation brake controller is configured to control the wheel brakes of the host vehicle to reduce a relative velocity between the host vehicle and the oncoming vehicle through activating at least one of:
 brake gain to increase braking if a driver of the road vehicle is already braking; and 
 auto brake to perform braking if a driver of the road vehicle is not already braking. 
 
     
     
         4 . The arrangement according to  claim 1  wherein the vehicle forward collision threat evaluation system is configured to compare the predicted future path of the oncoming vehicle with the predicted future path of the host vehicle to determine if a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable assuming freedom for performing avoidance maneuvers for both the host vehicle and the oncoming vehicle and using an assessment of the host vehicle's and the oncoming vehicle's possibilities to avoid an accident, such that a forward collision is determined as likely unavoidable if both the host vehicle and the oncoming vehicle need to perform evasive maneuvers at dynamic capabilities of the respective vehicles to avoid a forward collision. 
     
     
         5 . The arrangement according to  claim 1  wherein the vehicle forward collision threat evaluation system is configured to compare the predicted future path of the oncoming vehicle with the predicted future path of the host vehicle to determine if a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable assuming freedom for performing avoidance maneuvers for both the host vehicle and the oncoming vehicle and using an assessment of best case scenarios for the host vehicle's and the oncoming vehicle's possibilities to avoid an accident, such that a forward collision is determined as likely unavoidable if the considered best case scenarios for both the host vehicle and the oncoming vehicle are predicted to end in a forward collision. 
     
     
         6 . The arrangement according to  claim 1  wherein the vehicle forward collision threat evaluation system is arranged to:
 predict relative lateral vehicle positions of the host vehicle and the oncoming vehicle at a predicted collision instant; 
 predict relative lateral motion of the host vehicle and the oncoming vehicle at a predicted collision instant; 
 
       assume lateral avoidance maneuvers of the host vehicle and the oncoming vehicle; 
       assume longitudinal motion of the host vehicle and the oncoming vehicle, and 
       determine if a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable through assessing at least one of:
 predicted relative lateral vehicle positions of the host vehicle and the oncoming vehicle at a predicted collision instant; 
 predicted relative lateral motion of the host vehicle and the oncoming vehicle at a predicted collision instant; 
 
       assumed lateral avoidance maneuvers of the host vehicle and the oncoming vehicle; and 
       assumed longitudinal motion of the host vehicle and the oncoming vehicle. 
     
     
         7 . The arrangement according to  claim 6  wherein the vehicle forward collision threat evaluation system is configured to adjust at least one of the predictions and assumptions based on at least one of:
 data on a determined state of a driver of the host vehicle; 
 data on a configuration of host vehicle surrounding infrastructure; 
 data on a host vehicle traffic situation. 
 
     
     
         8 . The arrangement according to  claim 6  further comprising a warning arrangement configured to alert at least one of a driver of the host vehicle and a driver of the oncoming vehicle if determined that a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable. 
     
     
         9 . A road vehicle comprising the arrangement for mitigating a forward collision between a host vehicle and an oncoming vehicle according to  claim 1 . 
     
     
         10 . A method for mitigating a forward collision between a host vehicle and an oncoming vehicle, the host vehicle having one or more sensors arranged to monitor a road ahead of the host vehicle and a braking system connected to wheel brakes thereof, the method comprising:
 utilizing the one or more sensors to establish presence of an oncoming vehicle;   estimating parameters associated with the oncoming vehicle;   utilizing the estimated parameters to predict a future path of the oncoming vehicle;   utilizing host vehicle parameters to predict a future path of the host vehicle;   assessing the predicted future paths of the oncoming vehicle and of the host vehicle to determine if a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable assuming freedom for performing avoidance maneuvers for both the host vehicle and the oncoming vehicle in the prediction of the respective future paths of the host vehicle and the oncoming vehicle;   determining if a relative longitudinal velocity is above a first threshold; and   controlling the wheel brakes of the host vehicle to reduce a relative longitudinal velocity between the host vehicle and the oncoming vehicle at a predicted collision instant if determined that a forward collision between the host vehicle and the oncoming vehicle is likely unavoidable at a determined relative longitudinal velocity above a first threshold.   
     
     
         11 . The method according to  claim 10  wherein the estimated parameters include one or more of distance between the oncoming vehicle and the host vehicle, lateral and longitudinal velocity of the oncoming vehicle, relative longitudinal velocity between the host vehicle and the oncoming road vehicle, and lateral and longitudinal acceleration of the oncoming vehicle.